1. Field of the Invention
The invention relates to an electrical junction box for an automobile or the like, and in particular relates to an electrical junction box in which a connector lock for fixing a connector and a vehicle fixing portion for fixation to a vehicle.
2. Description of the Related Art
Electrical junction boxes have been used in automobiles and the like to facilitate the branching of wiring harnesses and connect wiring harnesses to electrical components, such as fuses and relays. U.S. Pat. No. 7,594,830 discloses such an electrical junction box with a box body formed by combining upper and lower cases. A circuit board, such as a printed circuit board, is housed inside the box body, and connection terminals project from the circuit board into a receptacle in the box body. Connectors provided at the terminals of wiring harnesses can be inserted into the receptacle and connected to the connection terminals of the circuit board. The electrical junction box also has a vehicle fixing portion for fixing the electrical junction box to a vehicle by being bolted to or engaged with a vehicle body panel, or being taped to wiring harnesses arranged in the vehicle.
The electrical junction box of U.S. Pat. No. 7,594,830 also has connector locks for fixing the connectors in the receptacle to prevent unexpected separation of the connectors.
The receptacle, the connector locks and the vehicle fixing portion of U.S. Pat. No. 7,594,830 all are provided on the upper case. Accordingly, there is the risk of flexural deformation of the upper case if the vehicle fixing portion is subjected to a load due to vibration or the like while the vehicle is traveling or when the electrical junction box is fixed to the vehicle while the connectors are connected. This flexural deformation could influence the connector locks so that the connector locks are released unexpectedly. The receptacle defines an open recess in the upper case. As a result, the vehicle fixing portion can only be formed on a side face of the upper case, thereby restricting the degree of freedom with respect to the shape of the vehicle fixing portion and the vehicle attachment direction.
To address this problem, the vehicle fixing portion could be separate from the receptacle and the connector locks by providing the receptacle and the connector lock on the upper case and providing the vehicle fixing portion on the lower case. However, with this structure, the upper case is fixed to the connectors by the connector locks, and the lower case is fixed to the vehicle by the vehicle fixing portion. Pulling forces on the wiring harnesses of the connectors due to vibration or the like while the vehicle is traveling could cause the upper case fixed to the connectors to displace in a direction of separation from the lower case because the vehicle fixing portion fixes the lower case to the vehicle. As a result, the connectors housed in the receptacle displace in the direction of separation from the lower case, and there is the risk of reduced contact points with the connection terminals of the circuit board. This therefore is not a desirable solution.
The invention was made in view of the above-described circumstances, and an object thereof is to improve the reliability of connection with connectors and improving the degree of freedom of attachment to a vehicle.